The present disclosure relates generally to medical devices for monitoring physiological parameters of a patient and, more particularly, to techniques for reducing power consumption of medical devices.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
In the field of medicine, doctors often desire to monitor certain physiological characteristics of their patients. Accordingly, a wide variety of devices have been developed for monitoring certain physiological characteristics of a patient. Such devices provide doctors and other healthcare personnel with the information they need to provide the best possible healthcare for their patients. As a result, such monitoring devices have become an indispensable part of modern medicine. For example, photoplethysmography is a common technique for monitoring physiological characteristics of a patient, and one device based upon photoplethysmography techniques is typically referred to as a pulse oximeter. Pulse oximeters may be used to measure and monitor various blood flow characteristics of a patient. A pulse oximeter may be utilized to monitor the blood oxygen saturation of hemoglobin in arterial blood, the volume of individual blood pulsations supplying the tissue, and/or the rate of blood pulsations corresponding to each heartbeat of a patient. In fact, the “pulse” in pulse oximetry refers to the time-varying amount of arterial blood in the tissue during each cardiac cycle.
A patient in a hospital setting may be monitored by a variety of medical devices, including devices based on photoplethysmography techniques. For example, a photoplethsymography (PPG) sensor acquires a photoplethsymographic (PPG) signal from a patient, and a patient monitor may use the PPG signal to determine one or more physiological parameters of the patient, such as, for example, blood oxygen saturation, pulse rate, and respiration rate. However, during periods of patient motion, the PPG signal may include artifacts and may have a low signal quality. For example, patient motion may cause optical components of the PPG sensor to lose contact with the skin, which may result in changes to the emitted and/or detected light and may result in signal artifacts and a decreased signal quality. Typically, the signal quality of the PPG signal or the signal quality of the physiological parameter determined based on the PPG signal is assessed, and the determined physiological parameter is weighted based on the signal quality and used in an algorithm to update the physiological parameter (e.g., on a display). However, if the signal quality is below a signal quality threshold, the determined physiological parameter may be zero weighted and, as a result, may not be used in the algorithm to update the physiological parameter. As such, the PPG signal may not provide useful information during periods of motion.